This project involves identification of cancer patterns among occupational groups that may reflect exposures in the work environment and investigation of methodological issues in occupational studies. Study groups are selected because of 1) known or potential exposure to established or suspect carcinogens, 2) prior reports suggesting an unusual cancer experience for the group, 3) requests by outside institutions, and 4) availability of useful resources. Resources used included employment and death records maintained by companies, labor unions or professional organizations, and records from government agencies. Studies during the past year include cohort mortality studies of persons employed in dry cleaning, non-agricultural pest control, chemical plants, non-ferrous smelters, taconite mines, jewelry manufacturing, embalming, welding, shipyards, chemical and medical laboratories, ship inspection, and hematite mining. Proportionate mortality studies being conducted involve tobacco workers, petrochemical workers, pottery workers, fur dyers, veterinarians, and embalmers. Death certificates are used to investigate occupational origins of leukemia, Hodgkin's disease, non-Hodgkin's lymphoma, multiple myeloma, and cancers of the prostate and colon.